%I #11 Jun 05 2024 04:26:46
%S 36,225,729,2304,2809,3481,5041,6084,7056,7569,8100,9216,9604,13456,
%T 14400,14641,15625,17956,23409,26244,26569,27889,32400,35344,41616,
%U 45369,46656,50176,50625,51076,52900,57600,58564,59536,63001,64009
%N Squares that are the sum of three distinct positive cubes.
%H Charles R Greathouse IV, <a href="/A112474/b112474.txt">Table of n, a(n) for n = 1..10000</a>
%e 36 = 6^2 = 1^3 + 2^3 + 3^3.
%t Lim=64009;sqlim=Floor[Sqrt[Lim]];cblim=Ceiling[Lim^(1/3)]; Select[Range[sqlim]^2,MemberQ[ Union[Total/@Subsets[Range[cblim]^3,{3}]],#]&] (* _James C. McMahon_, Jun 04 2024 *)
%o (PARI) has(n)=my(x3,z); for(x=sqrtnint(n\3,3)+1, sqrtnint(n,3), x3=x^3; for(y=sqrtnint((n-x3)\2,3)+1, min(x-1,sqrtnint(n-x3,3)), if(ispower(n-x3-y^3,3,&z) && z<y && z>0, return(1)))); 0
%o list(lim)=my(v=List(),t); for(n=6,sqrtint(lim\1), if(has(t=n^2), listput(v,t))); Vec(v) \\ _Charles R Greathouse IV_, Sep 20 2016
%Y Intersection of A000290 and A024975.
%K nonn
%O 1,1
%A _Rick L. Shepherd_, Sep 06 2005
%E Offset corrected by _Charles R Greathouse IV_, Sep 20 2016
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